I am asking here as there are many folks much more knowledgeable than I am.  Bought the bike after seeing it sitting at a local C-Store with a for sale sign.  Done without riding it, am actually glad I did not.

I live in town with a four lane road running next to the house. Watch the guy drive up to the house and park the bike to let me look at it.  Was offered the opportunity to take the bike for a ride , but declined as it was now the end of my day and I had had a couple of beers.  Asked the guy to ride it around the block and stuff it the garage.  Watched him leave and swing around the block at normal city speeds and sail her into the garage without incident.

A few days later I decide to take her out for a ride.  Got all suited up and head down the driveway (fairly steep approach to the road).  Hit the road at maybe 10 MPH and turn right  Immediate severe wobble/tank slapper.  Took me across the two lanes closest to the house and into the third lane headed face first into a 4x4. Fortunately he saw my problem and got out of my way.

I have owned three heavy bikes, a Goldwing and CBX and my current '12 Concours never experienced anything like this.

Web research shows possible problems like cupped tires (this has Dunlops in fair shape),  unequal air pressure in the suspension,  bad head bearings, swing arm looseness and improper tire pressure.

This incident was so severe I could not keep the bike headed where I wanted it.  Had no power rolled in and was basically coasting.  The only difference between me and the previous owner is weight.  I weigh a whopping 155 lbs and the previous owner and his wife probably weigh 400 or so lbs. together.  Could this cause this drastic of handling difference.

I'm about ready to have the bike hauled to the shop and let them sort this out.

Any suggestions appreciated.

Forgot to add the bike has 55,000 on it and is in excellent condition.---------------------------------------

Had it happen once on my '94 at about 35mph.  Scared the **** out of me.  My bet is on steering bearings being loose or worn.  If you take it in, I'd get the fork fluid changed and the wheel bearings checked out as well.  Could be a tire but that's hard to check until you replace it.

VERY loose steering head bearings.

Mine were pretty loose...to the point of being floppy.

Thanks guys,

Guess I'll invest in a tow truck and have it brought to the shop for inspection. Sounds like no way to safely ride the bike to the shop.  In some way I wish it was like the old days.  Grab the forks and shake and shimmy as best we could.  Replace what felt worn and ride on.

I had one of these, a '99 and they can tend to have a headshake if steering head is loose.  Mine did too, but not at 10 mph and it wouldn't launch me into different lanes.

Mine was between 45 and 50 mph, and on the decel, similar to what C10's will do if steering head is loose.

I was able to tune mine out by tightening the steering head bearings correctly AND making sure tire pressures were right, and that the front and rear suspension (particularly the rear) weren't really low on air.

You seem to have something pretty serious beyond those, unless the combined total of the symptoms I've listed, all being at their worst could do this. 

Keep us posted on what they find.

Okay,  there seems to be some interest in this issue and what is causing the problem so I will keep everyone informed.  My work schedule will keep me from getting the tow to the shop until Tuesday.  Don't know how long it will take for a resolution. Hope it's not to long.

Seems like a ride I will really enjoy for just cruising when this issue is resolved.

Just got back from the store.  Had to sit on it, start it and listen to the beautiful sound of the engine simply running.  For a 4 cylinder inline it sure sounds nice.  The exhaust even smells nice.

I know,  I am sick in the head.

you're not. We all like it, otherwise we'd be reading knitting forums 

otherwise we'd be reading knitting forums 

Now THAT would be sick in the head !

Voyager 12's are very nice for cruising or touring.  2 up is a breeze.  Lots of room for you and passenger.  Mine took a bit of suspension work / tweaking, then for its size it wasn't bad in the curves.  Smooth motor that has good power.  Motor is smooth.  Did I mention the smooth motor?  They are smooth.  Very smoothy.

Mine HAD to have a stacked set of Baker wind wings to survive in the heat of summer, especially if I ventured a state or three south of Michigan.